Hi sorry to hear your troubles. My son (16) has just started seeing his father after 3 yrs. He is now playing us off against each other, is allowed out till midnight, is allowed to smoke and basically do as he wants. At our home he must be in by 10.30 and do a couple of chores round the house. Guess who he likes best??
I know just how you feel - so torn inside. You love your kids but you hate how they are turning out and are powerless to change this. The guilt eats away at you. But if you are like me you have only ever done your best and it hurts like hell when its gone so wrong.
It may be a good idea to write them a letter as you say. Pour out your feelings, seal it up and keep it until you feel time is right for them to read it.
My 2 boys dont seem like me and my new husband very much. They treat our home like a hotel and even though their dad wished them dead 3 yrs ago, now they think hes great.
Life isnt fair and being a mum sucks huh? xxx